I really like Godless Capitalist's definition for his term "Political Infant":

Political infants are people who are unable to state their opponent's position in terms their opponent will agree with.

The concept offers powerful explanation for why so many debates are utterly fruitless: unless both sides to a discussion have progressed beyond political infancy, it's going to be impossible for them to get anywhere. The correlary of this is that in my own experience you're most likely to persuade someone of something by making clear you understand their view and comprehend the angle they take.

One of the consequences for debate in this country of the way our liberal elite is largely isolated from contrary views is the degree to which intelligent, open-minded people remain political infants because they are so uninformed about what the other side believes. As I have said on The Edge of England's Sword:

the isolated types who work for the BBC - whose main method of recruitment is the Guardian jobs section - have so few informative encounters with the majority of Britons who don't share their view of the world that they are unable to see anything wrong with such partial, question-begging journalism. They simply report the world as they see it: eurofederalism the only possible future for Britain, failing public services needing nothing but more tax money to set them right, street crime an invention of the Daily Mail but racism to be found under every stone. What? There are many reasoned, thoughtful and popular arguments against all of these positions? Well, in all the years they've been reading the Guardian and attending Islington tea parties, they've never come across them. So how can there be?

Almost every left-wing argument I have seen in favour of single-sex marriage or against free trade has shown this political infancy. Usually they are made as if the counter-arguments have never been made, because as far as the arguers are concerned, they never have been. While the BBC is happy to produce 'controversial' and 'challenging' documentaries in defence of all manner of far out left-wing views, making the arguments in their favour well-known if not well-believed, there is no equivalent for the Right. Mainstream conservative views on the NHS or family breakdown go unargued. As a result, even the most open-minded and genuinely tolerant liberals - the sort who think someone can disagree with them without being a bigot - end up political infants on certain key issues. The loss is everyone's.